“Less is better than more” seemed to be the theme of the studies selected by the American Society of Breast Surgeons (ASBS) for a news conference at its Annual Meeting, held in Chicago last month.
Researchers reported that:
* Postmenopausal women aged 55 to 75 with early-stage breast cancer can be safely treated with breast-conservative surgery without postoperative radiation therapy;
* Women who undergo mastectomy for breast cancer and choose prophylactic mastectomy for the contralateral breast have approximately double the risk of surgical complications; and
* Routine imaging studies conducted less than a year after a benign breast biopsy are an unnecessary drain on health care dollars.
A prospective, randomized study of postmenopausal women aged 55 to 75 with early-stage breast cancer treated with conservative surgery showed no statistically significant difference in the risk of local recurrence or overall survival between those who had postoperative radiation therapy and those who did not.
While surgical radiation after breast-conserving surgery is the generally accepted treatment for early-stage breast cancer, “we may be overtreating almost half of these patients,” said Corrado Tinterri, MD, Director of the Breast Unit at Humanitas Cancer Center, Istituto Clinico Humanitas, in Milan.
The RT 55-75 study, conducted at 11 centers in Italy, followed 749 patients for a median of nine years. Patients were age 55 to 75. Tumor size was 2.5 cm or less without an extensive intraductal component and without peri-tumoral vascular invasion.
Patients were randomly assigned to have surgery alone or surgery with postoperative breast irradiation of 50 Gy plus a 10 Gy boost.
At a median follow-up of 108 months, 3.2 percent (12/373) of patients who received radiation therapy had a recurrence (seven in the index quadrant, five in the other quadrant) vs. 4.3 percent (16/376) who did not receive radiation (seven in the index quadrant, nine in the other quadrant).
The rates of contralateral tumors were also approximately the same: 1.6 percent with radiation and 1.3 percent with no radiation; as were distant relapses: 7.0 and 7.5 percent, respectively.
And there was also no statistically significant difference in the risk of death between the two groups, 7.0 and 7.7 percent, respectively.
Tinterri noted that radiation carries significant costs to the medical system and the patient, and women who receive radiation after surgical resection may be unable to have satisfactory breast reconstruction if the tumor recurs and they are subsequently treated with mastectomy.
And because mastectomy generally is not accompanied by radiation, patients in areas where radiotherapy is not available would receive a mastectomy instead of conservative surgery.
In an interview after the meeting, Judy C. Boughey, MD, the Society's Publications Chair and Program Director of the Multidisciplinary Breast Surgery Fellowship at the Mayo Clinic, noted that many surgeons are questioning whether every aspect of treatment has a role, and if so, whether it is important and what the risks and benefits are.
“Obviously radiation does have a significant local-control benefit so we don't want to withhold radiation from women who would benefit, but we also don't want to radiate if they would do just as well without it. It comes down to selecting patients well, and older patients who tend to have slightly less aggressive tumors are probably a reasonable group to consider.”
Prophylactic Mastectomy Doubles Complication Rate
Surgeons have new data to share with the growing number of breast cancer patients considering prophylactic bilateral mastectomy.
A study from Canada of breast cancer patients in the American College of Surgeons National Surgery Quality Improvement Program (ACS NSQIP) database found a 5.8 percent rate of postsurgical wound complications for women choosing bilateral mastectomies, including infection and wound dehiscence, compared with 2.9 percent for women undergoing a single mastectomy.
In the study reported by Fahima Osman, a breast fellow at the University of Toronto, the overall surgical complication rates were 7.6 and 4.2 percent, respectively. Bilateral mastectomy also may delay chemotherapy or radiation therapy, she said.
“The findings are significant because the risk of future cancer in the opposite breast, without other risk factors, is extremely low, and there is no strong evidence that suggests that this procedure has a survival benefit in the majority of women with breast cancer,” she said.
Women may be choosing mastectomy of the healthy breast based on false assumptions about future cancer and survival benefits, she said. “For a woman who has an early-stage tumor in one breast with no other risk factors, the chance of suffering cancer in the contralateral breast is less than one percent per year, and this is especially true in the era of modern chemotherapy and endocrine therapy.”
Also asked for her opinion after the meeting, Deanna J. Attai, MD, an ASBS board member, said, “We are seeing more women who don't necessarily need a mastectomy and would be perfectly fine undergoing lumpectomy and radiation, who are choosing double mastectomy.”
Attai, in private practice at the Center for Breast Care, Inc., Burbank, CA, said some women cite experiences of friends or relatives who had disease recur in the contralateral breast, and others who say they do not want to have to undergo the extensive workup again. And some patients have the impression that with current reconstructive techniques, a double mastectomy would have acceptable cosmetic results.
“We're having to spend more time with our patients explaining that bilateral mastectomy is not necessarily a quick fix and doesn't necessarily mean you're done with cancer for life,” she said.
Boughey said that many surgeons at the meeting, herself included, thought it not that surprising that doing two procedures instead of one would double the complication rate. “What this study does provide is very important information for the surgeon to take back and discuss with the patient, and if the patient is at high risk for surgical complication then maybe the bilateral is not the best way to go.”
Smokers or patients with diabetes who have issues with wound healing would be at higher risk of complications in general, she said, or patients taking steroids, or taking blood thinners that would not be safe to discontinue. “For the standard, healthy young woman who wants the bilateral, I don't think this data would necessarily talk her out of it.” Cosmesis, breast symmetry after surgery, and other considerations also enter into the decision-making, she said.
“Women understand there is a risk of breast cancer per breast, and a risk of developing a surgical complication per site, and there are women who will weigh the two risks and want the bilateral anyway.”
Imaging at Less than 12 Months Is Costly
The yield for finding a malignancy with interval imaging in women diagnosed with benign breast lesions is extremely low, and interval testing at six months cannot be justified across the entire patient population, said the researcher presenting the third abstract discussed at the news conference, Demitra T. Manjoros, MD, a fellow at the Comprehensive Breast Center of Bryn Mawr Hospital in Pennsylvania.
In the study of 689 patients undergoing image-guided needle biopsy for breast cancer there in 2010, half of the 498 patients with benign lesions received at least one imaging exam during the year. Among 169 patients who had concordant findings between the radiologist and pathologist and who had interval imaging at less than 12 months after the benign biopsy, only one patient (0.06 percent) was diagnosed with a cancer.
A cost analysis showed that the cost of detecting that single cancer was approximately $193,000. And that particular patient had significant complicating factors that likely would have independently identified her as a candidate for early follow-up imaging anyway, Manjoros said.
“When results are concordant and the lesion is classified as benign, our study suggests that interval imaging is unnecessary, and the patient can safely wait for a full year for a routine screening mammogram.”
She noted that routine six- to 12-month imaging after a benign concordant breast biopsy is currently recommended as part of the National Comprehensive Cancer Network guidelines. “Imaging studies are costly and the goal is to provide exams that improve overall outcomes, vs. procedures that simply represent unnecessary testing. This study provides physicians with important information for making that choice.”
Attai commented that there are cases in which a six-month followup is reasonable, such as when a biopsy is done for calcifications and the pathology is benign but there are other calcifications in the breast the surgeon wants to follow.
“But if your only lesion or abnormality is the one that you biopsy and it is benign, then this study shows you don't necessarily need to go back and do a six-month follow-up imaging.”